Oilpan: Prepare to move EventDispatchMediator to Oilpan heap.

Source/core/events/EventDispatchMediator.cpp

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 18 matching lines @@
  */
 
 #include "config.h"
 #include "core/events/EventDispatchMediator.h"
 
 #include "core/events/Event.h"
 #include "core/events/EventDispatcher.h"
 
 namespace WebCore {
 
-PassRefPtr<EventDispatchMediator> EventDispatchMediator::create(PassRefPtrWillBeRawPtr<Event> event)
+PassRefPtrWillBeRawPtr<EventDispatchMediator> EventDispatchMediator::create(PassRefPtrWillBeRawPtr<Event> event)
 {
-    return adoptRef(new EventDispatchMediator(event));
+    return adoptRefWillBeNoop(new EventDispatchMediator(event));
 }
 
 EventDispatchMediator::EventDispatchMediator(PassRefPtrWillBeRawPtr<Event> event)
     : m_event(event)
 {
 }
 
+void EventDispatchMediator::trace(Visitor* visitor)
+{
+    visitor->trace(m_event);
+}
+
 bool EventDispatchMediator::dispatchEvent(EventDispatcher* dispatcher) const
 {
     ASSERT(m_event.get() == dispatcher->event());
     return dispatcher->dispatch();
 }
 
 } // namespace WebCore